Friday, January 09, 2015

Subliminal Strengthening

Levy et al. make the interesting observation that presenting subliminal positive age stereotypes to older people has a greater effect than similar explicit interventions:

Negative age stereotypes that older individuals assimilate from their culture predict detrimental outcomes, including worse physical function. We examined, for the first time, whether positive age stereotypes, presented subliminally across multiple sessions in the community, would lead to improved outcomes. Each of 100 older individuals (age = 61–99 years, M = 81) was randomly assigned to an implicit-positive-age-stereotype-intervention group, an explicit-positive-age-stereotype-intervention group, a combined implicit- and explicit-positive-age-stereotype-intervention group, or a control group. Interventions occurred at four 1-week intervals. The implicit intervention strengthened positive age stereotypes, which strengthened positive self-perceptions of aging, which, in turn, improved physical function. The improvement in these outcomes continued for 3 weeks after the last intervention session. Further, negative age stereotypes and negative self-perceptions of aging were weakened. For all outcomes, the implicit intervention’s impact was greater than the explicit intervention’s impact. The physical-function effect of the implicit intervention surpassed a previous study’s 6-month-exercise-intervention’s effect with participants of similar ages. The current study’s findings demonstrate the potential of directing implicit processes toward physical-function enhancement over time.

The study they cite as showing less effect of exercise than subliminal priming used the same standard "Short Physical Performance Battery" to assess changes in physical ability caused by the interventions. This test assesses strength, gait, and balance by examining (a) time to rise from a chair and return to the seated position five times, (b) time to walk 8 feet, and (c) ability to stand with feet together in the side-by-side, semi-tandem, and tandem positions for 10 s. Possible scores range from 0 to 12, with a higher score indicating better physical performance. Older individuals who receive lower scores on this measure have increased risk of disability, nursing-home placement, and mortality.